Survivors after nuclear attack

In the new film “The Divide,” a small group of people finds itself taking shelter in the sprawling basement of its New York City apartment building after a nuclear attack. Without a clear idea of what things might be like outside, or even who is attacking, they dig in for the long haul, scrounging for supplies and hoping to just wait it out.

Director Xavier Gens seems to have set out to fashion a taut, under-siege thriller, but he never lets the innate drama of the situation play out; too often, events are accompanied by loud thumps and whooshes on the soundtrack. Likewise, the screenplay by Karl Mueller and Eron Sheean aspires to use the movie’s gritty post-apocalyptic chamber piece setting as a vehicle for an existential exploration of human nature, but the writing simply doesn’t hold up under the weight of those bigger ideas.

Veteran character actor Michael Biehn (“The Terminator”) seems best attuned to a mix of knowingness and slight hamminess on display here, but his character is sidelined for a long stretch and his absence from the screen drains the film of its best energy.

As the story plays out as an increasingly raw dynamic of sex and power among the survivors, the film’s basic point — the real enemy is not out there, it is in here, it is us — gets made early and often, causing “The Divide” to feel increasingly repetitive. When a character swims through raw sewage to escape at the film’s climax, it’s hard not feel a certain solidarity. “The Divide.” Unrated. Running time: 1 hour, 50 minutes. At the Nuart, West Los Angeles.